62 resultados para germanium
Resumo:
Eight new compounds of (GeCH2CH (CH3) COOAr)(2)O-3 type were synthesized. Four of them were tested for antitumor activities against Hela cells in vitro, showing considerable tumor inhibitory activities.
Resumo:
This paper reports the results of the crystal and molecular structures, CI-MS and FAB-MS analyse of Cl3GeCH2CH2COOH and Cl3GeCH(CH3)CH2COOH. The characters and active parts of these molecules are also discussed
Resumo:
Three samples of β-carboxyethyl-germanium sesquioxide (Ge-132) have been prepared with different methods. Their IR, Raman, XPS, TG-DTA and FAB-MS spectra are quite different and indicate that they have different degree of polymerization and molecule structures. In the aqeous solution, all of them interaot strongly with fructose, but not with polypeptides such as GSH and GSSG. This faot may be important in understanding the bioactivity of Ge-132.
Resumo:
The impacts of germanic acid Ge(OH)(4) on the growth of Psuedonitzschia pungens f. multiseries and on the production of the algal toxin, domoic acid, were studied. The results showed that germanic acid in the range of concentrations could inhibit the growth of the algal cells and the inhibition was enhancing with the concentrations of germanic acid increasing. Germanic acid also could inhibit the production of the algal toxin, domoic acid in cells and the inhibition reached up to 100% at Ge/Si = 35. Based on the results, the mechanism was discussed.
Resumo:
Mn+ irons were implanted to n-type Ge(1 1 1) single crystal at room temperature with an energy of 100 keV and a dose of 3 x 10(16) cm(-2). Subsequently annealing was performed at 400degreesC for 1 h under flowing nitrogen gas. X-ray diffraction measurements show that as-implanted sample is amorphous and the structure of crystal is restored after annealing. Polycrystalline germanium is formed in annealed sample. There are no new phases found except germanium. The samples surface morphologies indicate that annealed sample has island-like feature while there is no such kind of characteristic in as-implanted sample. The elemental composition of annealed sample was analyzed by Auger electron spectroscopy. It shows that manganese ions are deeply implanted into germanium substrate and the highest manganese atomic concentration is 8% at the depth of 120 nm. The magnetic properties of samples were investigated by an alternating gradient magnetometer. The annealed sample shows ferromagnetic behavior at room temperature.
Resumo:
Infrared (IR) luminescence covering 1.1 to similar to 1.6 mu m wavelength region was observed from bismuth-doped barium silicate glasses, excited by a laser diode at 808 nm wavelength region, at room temperature. The peak of the IR luminescence appears at 1325 nm. A full width half-maximum (FWHM) and the lifetime of the fluorescence is more than 200 nm and 400 mu s, respectively. The fluorescence intensity increases with Al2O3 content, but decreases with BaO content. We suggest that the IR luminescence should be ascribed to the low valence state of bismuth Bi2+ or Bi+, and Al3+ ions play an indirect dispersing role for the infrared luminescent centers.